JP2612956B2 - Method for determining exposure amount of copying machine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for determining an exposure amount of a copying apparatus, and more particularly, to an exposure amount of a copying apparatus such as a hard copy apparatus such as a photographic printing apparatus, a camera, and a laser printer. The present invention relates to a method for determining an exposure amount of a copying apparatus which is determined using fuzzy inference.

[Problems to be solved by conventional technology and invention]

2. Description of the Related Art Conventionally, in a color photographic printing apparatus, an original screen recorded on a film, that is, an original image is divided into a large number of pieces, photometry is performed, and image feature values of a plurality of predetermined regions are determined from photometric data obtained by the photometry. That is, an average density, a maximum density, a minimum density, and the like are obtained, and a printing exposure amount is determined based on an image feature amount of each area. in this case,
Since there is a high probability that the main part exists in the center part of the original screen, the image feature amount is often obtained by dividing the image into a plurality of areas including the center part and other areas. Then, the weight of the image feature amount in the region including the central portion is increased to determine the printing exposure amount.

In the case of similar original screens shown in FIGS. 2 (1) and (2), the same printing exposure amount should be determined, but the image feature amount of the area 12 including the center of each original screen is different. In the exposure amount determination method, since the exposure amount is determined by weighting the image feature amount of the region including the center, the exposure amount is not the same, and the exposure amount for a similar original screen varies. The same applies to each exposure amount, that is, the exposure amount when the camera position is slightly different with respect to the same subject in camera photographing of a method in which exposure is determined based on photometric values from a plurality of photometric elements, and in a photographic printing device. It also occurs at each printing exposure when the set position of the film on the film carrier varies when printing the same original screen a plurality of times.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and it is possible to expose the same or similar color image when copying a color original image such as a subject, an image recorded on a color film, and a color hard copy original. It is an object of the present invention to provide a method for determining an exposure amount of a copying apparatus in which the amount does not vary.

[Means for solving the problem]

In order to achieve the above object, the present invention provides an exposure amount determining method for a copying apparatus that determines an exposure amount based on an exposure amount arithmetic expression defined for each of a plurality of pre-classified patterns. To obtain a plurality of feature amounts of the color original image from the data obtained by the photometry, and determine the degree of coincidence with each determination condition for determining the magnitude of the feature amount defined for each of the feature amounts. Determine, determine the degree of coincidence for each of the plurality of patterns using a plurality of degrees of coincidence with each determination condition, determine the weight for each pattern from the degree of coincidence with the pattern, to each of the exposure amount determined from the exposure amount calculation formula The exposure amount is determined by assigning the weight.

In the present invention, the degree of coincidence with the pattern can be determined by the product of the degree of coincidence with the determination condition.

In addition, the degree of coincidence with the determination condition is determined according to the difference between a predetermined value and the feature amount. When the difference is 0, the degree of coincidence is 0 and 1.
It can be set to a value between 0 and the degree of coincidence with the determination condition is determined based on the appearance frequency distribution of the magnitude of the feature amount, and the degree of coincidence of the value with the highest appearance frequency is 0 and 1.0. It can also be set to a value between.

[Action]

The present invention, when determining the exposure amount based on the exposure amount calculation formula determined for each of a plurality of patterns that have been classified in advance, by dividing the front of the color original image into a large number of photometry, and from the data obtained by photometry A plurality of feature values of the color original image are obtained. As the feature amount, an average density, a maximum density, a minimum density, a density difference of each photometry point, a density histogram shape, a color, or the like of each area when the color image is divided into a plurality of areas, or a value obtained by combining these, or An average luminance, a maximum luminance, a minimum luminance, or a combination thereof can be used. Next, the degree of coincidence with each determination condition for determining the magnitude of the feature amount determined for each feature amount is obtained. By using a plurality of coincidences with the determination condition and, for example, calculating a product of the coincidences, a coincidence for each of the plurality of patterns is determined, and a weight for each pattern is determined from the coincidence for this pattern. This weight increases as the degree of coincidence with the pattern increases. Then, a final exposure amount is determined by weighting each of the exposure amounts determined from the exposure amount calculation formula and adding the weights, for example.

The degree of coincidence with the determination condition can be determined according to the difference between the predetermined value and the feature value. At this time, the degree of coincidence when the difference is 0 is set to a value between 0 and 1.0, preferably 0.5. Also, the degree of coincidence with the determination condition is determined based on the appearance frequency distribution of the magnitude of the feature quantity, and the degree of coincidence with the feature quantity with the highest appearance frequency is set to a value between 0 and 1.0, preferably 0.5. Is also good.

〔The invention's effect〕

As described above, according to the present invention, the weight for the pattern is determined from the degree of coincidence between the feature amount of the color original image and the determination condition, and the respective exposure amounts determined from the exposure amount calculation formula are weighted to obtain the final exposure amount. Is determined, it is possible to reduce the variation in the exposure amount for the same or similar color original image. Also, good repetitive reproducibility can be obtained in determining the exposure amount of the same color original image.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In the first embodiment, the present invention is applied to a color photographic printing apparatus, and FIG. 3 schematically shows a color photographic printing apparatus to which the present invention can be applied. Below the color negative film 20 loaded in the negative carrier and transported to the printing unit, a lamp house 10 having a mirror box 18 and a halogen lamp is arranged. A light control filter 60 is arranged between the mirror box 18 and the lamp house 10. As is well known, the dimming filter 60 includes three color filters of a Y (yellow) filter, an M (magenta) film, and a C (cyan) filter.

Above the negative film 20, a lens 22, a black shutter 24, and a color paper 26 are arranged in this order, and a light beam emitted from the lamp house 10 and transmitted through the light control filter 60, the mirror box 18, and the negative film 20 is a lens. twenty two
To form an image on the color paper 26.

The sensor is located in a direction inclined with respect to the optical axis of the imaging optical system and at a position where the image density of the negative film 20 can be measured.
28 are located. The sensor 28 is composed of a two-dimensional image sensor or line sensor composed of a CCD (Charge Coupled Device), and converts a negative image into a large number of pixels as shown in FIG.
The surface is divided into Sn and photometry is performed along the scanning line SL. in this case,
The photometry of each pixel is performed for the B, G, and R3 primary colors.

The sensor 28 is connected to an exposure control circuit 40 that calculates an exposure amount control value and controls the dimming filter 60 via the driver 30 to control the exposure amount. The exposure control circuit 40 includes a program for an exposure control routine shown in FIG. 1, a read-only memory (ROM) storing a membership function described below, a random access memory (RAM), and a central processing unit (CPU). And a microcomputer provided with It is preferable that the microcomputer has a digital fuzzy chip.

Next, a fuzzy control rule according to the present embodiment will be described. First, in the present embodiment, as shown in FIG. 5, the screen of the color film is divided into three regions: a central region R ₁ , a peripheral lower half region R ₂ , and a peripheral upper half region R ₃ . Also, each area
The following feature amounts V ₁ , V ₂ , V ₃ , and V ₄ are employed as feature amounts obtained from photometric data included in R ₁ , R ₂ , and R ₃ . The feature values V ₁ , V ₂ , V ₃ , and V ₄ are obtained for each of the _three colors R, G, and B, but will be described below without distinction.

V ₁ : average density of central region R _1- average density of peripheral region of screen (region obtained by adding peripheral lower half region R ₂ and peripheral upper half region R ₃ ) V ₂ : full screen (central region R ₁₎ , the average concentration of the added peripheral lower half region R ₂ and the peripheral upper half region R ₃ regions) - full screen minimum density V _3: screen peripheral region of the density difference is small portions between each of the photometry points of the periphery of the screen area Area ratio V ₄ : maximum density of lower half region R ₂ -minimum density of entire screen As fuzzy control rules, the following five rules (1) to (5) are used in the form of if to then.

(1) If the smaller the characteristic quantity V ₁ is small and the feature quantity V _2, to the final exposure amount of the exposure amount obtained with an exposure amount arithmetic expression F ₁ (value when actually controlling the amount of exposure) The degree of reflection, that is, the weight is increased.

(2) If the larger the and characteristic amount V ₂ smaller feature quantity V _1, to increase the reflection degree for the final exposure of the resulting exposure using the exposure amount calculating equation F _2.

(3) If the larger the feature quantity V ₁ is large and the feature quantity V _3, to increase the reflection degree for the final exposure of the resulting exposure using the exposure amount calculating equation F _3.

(4) If the smaller the characteristic quantity V ₁ is large and the feature quantity V ₃ is small and the feature quantity V _4, to increase the reflection degree for the final exposure of the resulting exposure using the exposure amount calculating equation F ₄ .

(5) If the larger the feature quantity V ₁ is large and the feature quantity V ₃ is small and the feature quantity V _4, to increase the reflection degree for the final exposure of the resulting exposure using the exposure amount calculating equation F ₅ .

The language values, such as large and small, are feature quantities described below.
It is quantified by the membership function of V _i (where i = 1, 2, 3, 4). This membership function is determined as follows. First, similar screens actually have different image structures and the like, but in many cases, it is assumed that only the position of the main subject in the screen is different, and the similarity of the screen is compared with the photometry area of the screen and the sensor. Is assumed to be equivalent to the case where is shifted. Under this assumption, the position of the photometry area with respect to the screen is shifted stepwise to the left and right, and photometry is performed on the feature value V _0i (predetermined value) when the photometry area indicated by the broken line in FIG. the difference ΔV feature quantity V _i 'when shifted area
A histogram of _i (= V _i ′ −V _0i ) is created. 6 (A) and 6 (C) show the photometry area to the right from the normal position, respectively.
The state shifted to the left is shown. This histogram is as shown in FIG. 7 (B). The part where the frequency of the histogram is the highest is the part where the feature amount does not change despite the shift of the photometric area (difference ΔV _i = 0), which means that the similarity of the screen is the highest.

Accordingly membership value of the feature quantity V _i corresponding to the point where the frequency of the histogram is maximized, i.e. degree of coincidence to determine the membership functions to 0.5. Incidentally, the membership value of the feature quantity V _i corresponding to the point where the frequency of the histogram is maximized, can be set to a value between 0.0 and 1.0. Further, the position where the membership value becomes 1.0 or 0.0 may match the position where the frequency of the histogram is minimum or near this position, or may match the position where the frequency is between the maximum and minimum. .

When the membership function is determined by the above method, the feature amount V ₁
Is a ninth member function for the above rule (1).
FIG. 8 (A), FIG. 8 (B) for rule (2), FIG. 8 (C) for rule (3), FIG. 8 (D) for rule (4), The rule (5) is determined as shown in FIG. 8 (E). The membership function of the feature quantity V _1, each membership value V ₁ = K ₁ (e.g., 72, the value is 100 times the concentration value, the same applies hereinafter) is set to 0.5, indicating the position in dotted lines . As shown in FIG. 8 (F) for the rule (1) and FIG. 8 (G) for the rule (2), the membership function of the feature quantity V ₂ is V ₂ = It is determined that the membership value becomes 0.5 at K ₂ (for example, 61). Further, the membership function for the feature amount V ₃ is as shown in FIG. 8 (H) for rule (3), FIG. 8 (I) for rule (4), and FIG. 8 (I) for rule (5). As shown in FIG. 8 (J), the membership value is determined to be 0.5 when V ₃ = K ₃ (for example, 13). Then, as shown in FIG. 8 (K) for the rule (4) and FIG. 8 (L) for the rule (5), the membership function for the feature amount V ₄ is V ₄ = K _{At 4} (eg, 106), the membership value is determined to be 0.5. These membership functions, which define the determination condition, indicates that the higher the degree of coincidence determination condition feature quantity V _i in accordance with the membership value becomes larger.

Note that represents the size distribution of the value of the feature quantity V _i in the histogram, the degree of coincidence for the distribution with the largest value a value between 0 and 1.0, preferably may be set to 0.5. Incidentally, the exposure amount calculating equation F ₁ when the V ₁ <K ₁ and V ₂ <K ₂ (pattern 1), the exposure amount calculating equation F ₂ when the V ₁ <K ₁ and V ₂ ≧ K ₂ (pattern 2), the exposure amount calculating equation F ₃ when V ₁ ≧ K ₁ and V ₃ ≧ K ₃ is (pattern 3), the exposure amount calculating equation F ₄ is V ₁ ≧ K ₁ and V ₃ <K ₃ and V ₄ < K when ₄ (pattern 4), the exposure amount calculating equation F ₅ is V ₁ ≧
When K ₁ and V ₃ <K ₃ and V ₃ ≧ K ₄ (pattern 5), the values are determined so as to obtain the optimum exposure.

The membership function and the exposure calculation formula determined as described above are stored in the ROM of the exposure control circuit 40 in advance.

Next, an exposure control routine of this embodiment for controlling the exposure amount using the above membership function will be described with reference to FIG. In step 100, the photometric data detected by the sensor 28 is fetched, and in step 102, each of the photometric data is divided into regions R ₁ , R ₂ , R ₃ as shown in FIG.
Is determined, and all the photometric data are classified. In step 104, using the classified photometric data as described above, it calculates the feature quantity V ₁ ~V ₄ described above. In the next step 106, it calculates the matching degree corresponding to the feature quantity V ₁ ~V ₄ from the membership function shown in FIG. 8 in accordance with the fuzzy control rules described above (1) to (5), i.e. feature amount The degree of coincidence with the judgment condition is calculated for V _{1 to} V ₄ , and the product wi of the degree of coincidence for each of rules (1) to (5), that is, the degree of coincidence for each of patterns 1 to 5, is calculated in step 108 I do. Since the degree of coincidence with respect to this pattern represents the degree of reflection of the exposure amount obtained from each exposure amount calculation formula with respect to the final exposure amount, it will be described below as the degree of reflection. In the example shown in FIG. 8, for rule (1),
Coincidence degree for the feature quantity V _1, that is, the membership value 0.
7 (represented by the solid line, the same below), since the degree of coincidence for the feature quantity V ₂ is 0.4, reflecting the degree becomes 0.7 × 0.4 = 0.28. For Rule (2), the degree of coincidence of 0.7 for the feature quantity V _1,
Since the degree of coincidence with the feature amount V ₂ is 0.6, the reflection degree w ₂ is
0.7 x 0.6 = 0.42. For rule (3), the feature value
Degree of coincidence 0.3 for V _1, the degree of coincidence for the feature quantity V ₃ 0
Because it is, reflection degree w ₃ becomes 0.3 × 0 = 0. Rule (4) For, since the degree of coincidence for the feature quantity V ₁ is 0.3, the degree of coincidence for the feature quantity V ₃ is 1.0, it is 0.9 degree of coincidence for the feature quantity V _4, reflection degree w ₄ is 0.3 × 1.0 × 0.9 = 0.27.

Since for the rule (5), the degree of coincidence for the feature quantity V ₁ is 0.3, the degree of coincidence for the feature quantity V ₃ is 1.0, it is 0.1 degree of coincidence for the feature quantity V _4, reflection degree w ₅ 0.3 × 1.0 × 0.1
= 0.03.

In the next step 110, a reflection degree normalization process is performed according to the following equation.

By normalizing in this way, In the next step 112, the exposure f
calculating a i (however, i = 1,2 ... 5), the integrated value as shown in by adding a weight corresponding to the normalized degree of reflection W _i to each of the exposure amount fi (2) equation in step 114 Is the final exposure amount X.

Then, by driving the driver 30 with the exposure control value determined by the final exposure amount X, the position of the light control filter 60 is controlled to control the exposure amount.

The distribution of the change in the exposure amount of the present embodiment (fuzzy inference by algebraic product) due to the film set position shift when the exposure amount is controlled as described above using the same original image is shown in a conventional example (current) and a comparative example ( FIG. 9 shows a comparison with the distribution of "fuzzy inference based on logical product". In Fig. 9, ΔDK
Indicates a change in the exposure amount due to a shift in the set position of the film. A change of 0.5 corresponds to a change in the exposure amount of 10%. In addition,
Fuzzy inference based on logical product is performed according to the above rules (1) to (5).
Is used in the conclusion part (then ~). As can be understood from the figure, in fuzzy inference based on algebraic product and fuzzy inference based on logical product, a portion where ΔDK is small (0.0 to 0.5, −0.5 to
0.0), the distribution is higher than the current distribution, and it can be seen that the rate of small change in the exposure amount is high even if the film setting position is shifted. In addition, the fuzzy inference based on the algebraic product of the present embodiment has a smaller change in the exposure amount with respect to the film set position deviation than the fuzzy inference based on the logical product of the comparative example. Better results are obtained when using.

As described above, according to the present embodiment, even if the film setting position is shifted, the change in the exposure amount is small, and the difference in the exposure amount for similar images is also small, and a series of similar images are reproduced as uniform colors and densities. Will be done.

Next, a second embodiment of the present invention will be described. In this embodiment, the present invention is applied to exposure control in a camera.
In the case of a camera, exposure is often referred to as exposure, and therefore, the description will be made using the term "exposure" below. In the present embodiment, as shown in FIG. 10 (1), a photographing screen viewed with a viewfinder is surrounded by a center area A including a focus point (a point where a main subject is present), and a periphery of the center area A. It is divided into three regions, a region B and a region C existing outside the region B. In this embodiment, as shown in FIG. 10 (2), for metering a Viewfinder photometer using six photometric element P ₁ to P _6. Or a photometer comprising a plurality of photometric elements or more and a plurality of distance meters, the area A is set at the position of the focus point by automatically detecting the focus point,
It is preferable that B and C are determined. In addition, the following feature amounts B ₁ and B ₂ are adopted as feature amounts obtained from the photometric data included in each of the regions A, B, and C.

B ₁ = Ba−Bbc B ₂ = Bab−Bc where Ba is the average luminance of the area A, Bc is the average luminance of the area C, Bab is the average luminance of the area obtained by adding the areas A and B, B
bc is the average luminance of the area obtained by adding the area B and the area C.

The following five rules are used as fuzzy control rules.

(1) If the smaller the characteristic quantity B _1, it is determined that the super-backlit subjects.

(2) If the feature value B ₁ is medium and the feature value B ₂
If is smaller, it is determined that the subject is backlit.

(3) If the feature value B ₁ is medium and the feature value B ₂
If is a medium size, it is determined that low-contrast shooting has been performed.

(4) If the feature value B ₁ is medium and the feature value B ₂
If is larger, it is determined that the photographing is in direct light.

(5) If the feature amount B ₁ determines that it spotlights shooting large.

The language value of the above rule is quantified by the membership function described below. That is, the membership function of the feature amount B ₁ is as shown in FIG. 1 (A) for the rule (1), FIG. 11 (B) for the rule (2), and for the rule (3). For FIG. 11 (C) and Rule (4), FIG. 11 (D),
Rule (5) is determined as shown in FIG. 11 (E). In the membership function of FIG. 11 (A), B ₁ =
The membership value is set to 0.5 at α1, and the first
1 In the membership functions of FIGS. (B) to (D), B ₁ = α1
And when B ₁ = β1, the membership value is set to 0.5, and in the membership function of FIG. 11 (E), B ₁ =
The membership value is set to 0.5 when β1. Also, the membership function of the feature amount B ₂ is as shown in FIG. 11 (F) for rule (2), FIG. 11 (G) for rule (3), and FIG. 11 (G) for rule (4). It is determined as shown in FIG. 11 (H). The membership function in FIG. 11 (F) is B ₂ = α1, the membership value is 0.5, and FIG. 11 (G)
As membership value of 0.5, the membership function of FIG. 11 (H) has membership value B ₂ = .beta.2 becomes 0.5 when the membership function of the _{B 2 = α2, B 2 =} β2 So that each is set. As described in FIG. 7, these membership functions shift the camera slightly stepwise with respect to the normal position, and create a histogram of the difference between the characteristic amount at the normal position and the characteristic amount when the camera is shifted. The difference is 0
Is determined so that the membership value becomes 0.5 at. The membership value when the difference is 0 may be any value between 0 and 1.0. Further, as described above, the membership function may be determined from the distribution of the feature amount.

Also, when it is determined that the subject is in a super-backlit shooting mode, the exposure calculation expression E ₁
In heavier the weight of the exposure amount obtained, heavier weights exposure amount determined by the exposure calculation equation E ₂ when it is determined that the backlit scenes,
Exposure calculation formula E ₃
The weight of the exposure amount obtained in step ₄ is increased, and when it is determined that the subject is in normal light shooting, the weight of the exposure amount obtained by the exposure calculation equation E4 is increased.
Exposure calculation equation E ₅ is when it is determined that the spotlight photographing
The final exposure amount is calculated by increasing the weight of the exposure amount obtained in (1). The exposure arithmetic expressions E _{1 to} E ₅ are expressed by the following luminances BV _{1 to} BV ₅
Is used to calculate the amount of exposure.

Incidentally, k ₁₀ to k ₆₁ are constants, Bb is the average luminance of the area B, Bab
_min is the minimum luminance of the area obtained by adding the area A and the area B, Bab
_max is the maximum luminance of the area obtained by adding the area A and the area B.

Next, an exposure control routine according to the present embodiment will be described with reference to FIG. In FIG. 12, parts corresponding to those in FIG. 1 are denoted by the same reference numerals, and detailed description is omitted. In step 90, photometric data and focus point information measured by a photometer having a plurality of photometric elements built in the camera are taken in. In step 92, the position of the area A is set so that the focus position is located at the center of the area A. Is determined, and the position of the area B is determined so that the area A is located at the center. In the case of one distance measuring device, the areas A, B, and C are fixed because the focus point is located at the center. Steps
At 102, the photometric data belonging to the area determined as described above is determined and the photometric data is classified as in the first embodiment.
In step 104, feature amounts B ₁ and B ₂ are calculated. In step 106 calculates the matching degree from the membership function shown in FIG. 11, as well the degree of coincidence of the product in the first embodiment, calculates the normalized reflected degree, and calculates an exposure amount E _i as above The exposure amount is controlled by obtaining the final exposure amount Y.

Conventionally, selective photometric values such as maximum luminance and minimum luminance are selected or not selected due to a camera position shift, and thus have an unstable influence on exposure determination, but this embodiment increases stability. However, it is possible to determine an appropriate exposure amount even for a small main subject.

According to the present embodiment, even when the same subject is photographed with the camera position shifted or a similar subject is photographed, a series of images are photographed with the same density and color.

Although an example in which the screen is divided into three areas has been described above, the present invention is not limited to this, and the screen may be divided into four or more as necessary. Further, the membership function may be changed as needed.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an exposure control routine according to a first embodiment of the present invention, FIGS. 2 (1) and 2 (2) are diagrams showing the positions of photometric areas with respect to similar screens, and FIG. FIG. 4 is a schematic diagram of a possible color photographic printing apparatus, FIG. 4 is a diagram showing a state in which the sensor measures the light by dividing the screen into planes, FIG. 5 is a diagram showing a state in which the screen is divided, and FIG. , (B), (C)
Is a diagram showing the displacement of the photometry area with respect to the screen, FIG. 7 is a diagram showing the relationship between the histogram and the membership function, FIG. 8 is a diagram showing the membership function and the like of the first embodiment, FIG. FIG. 9 is a diagram showing the distribution of the change in the exposure amount due to the displacement of the film setting position, FIG. 10 (1) is a diagram showing the screen division area of the second embodiment, and FIG. 10 (2) is the second embodiment. FIG. 11 is a diagram showing a membership function and the like of the second embodiment, and FIG. 12 is a flowchart showing an exposure control routine of the second embodiment. R ₁ , R ₂ , R ₃ , A, B, C... Area, 40... Exposure control circuit.

Claims (4)

(57) [Claims] An exposure determining method for a copying apparatus that determines an exposure based on an exposure calculation formula defined for each of a plurality of patterns classified in advance. Obtaining a plurality of feature amounts of the original curler image from data obtained by photometry, obtaining a degree of coincidence with each determination condition for determining the size of the feature amount defined for each of the feature amounts, Determining the degree of coincidence for each of the plurality of patterns using a plurality of degrees of coincidence, determining the weight for each pattern from the degree of coincidence for the pattern, and applying the weight to each of the exposure amounts determined from the exposure amount calculation formula. A method for determining an exposure amount of a copying apparatus, comprising determining an exposure amount. 2. A method according to claim 1, wherein the degree of coincidence with the pattern is determined by a product of the degree of coincidence with the determination condition. 3. A degree of coincidence with the determination condition is determined according to a difference between a predetermined value and the feature amount.
3. The method according to claim 1, wherein the exposure value is set to a value between 1.0 and 1.0. 4. The method according to claim 1, wherein the degree of coincidence with the determination condition is determined based on an appearance frequency distribution of the magnitude of the feature amount, and the degree of coincidence of the value having the highest appearance frequency is set to a value between 0 and 1.0. Item (1) or (2), the method for determining the exposure amount of the copying apparatus.